FORGET ABOUT IT, KID! Derek Jeter celebrates with Melky Mesa, who committed a baserunning blunder in the 13th inning of the Yankees’ 10-9 come-from-behind victory in 14 innings yesterday at the Stadium.Paul J. Bereswill

All you need to know about this game — arguably the craziest day of the season, in a characteristically eventful Yankees campaign — is that for all of the great stuff that went down over 14 innings, 5 hours and 43 minutes, manager Joe Girardi gave his lineup card to the kid who missed third base.

The kid who nearly lost the game. That could have snowballed into a lost season.

Oh, man, could things have turned ugly for the Yankees and their September call-up Mesa if not for the generosity of the Athletics. A marathon of misplays concluded when Oakland first baseman Brandon Moss failed to glove Eduardo Nunez’s two-out grounder, allowing Ichiro Suzuki to score for a 10-9 Yankees victory over the A’s and securing the Yankees’ one-game American League East lead over the victorious (again) Orioles.

They were poised to win two batters prior, when Alex Rodriguez slammed a one-out base hit up the middle with Mesa (pinch-running for Eric Chavez, who singled) on second base. Rodriguez raised his arms in triumph, only to see Mesa step over third base and retreat to the bag. Mesa stood in the dugout, having been forced at home on a Robinson Cano grounder, when Moss handed the Yankees the victory.

“That would’ve been a tough one for this kid to swallow,” Girardi said of Mesa. “A lot of the guys gave him hugs. We told him, ‘Keep your head up.’ No one’s going to be perfect out there. We’ve all made mistakes where we’ve fumbled balls. We’ve forgotten how many outs there were. We’ve missed bases.

The Yankees survived a brutal start by Ivan Nova, who lasted just 2 1/3 innings, and they exhibited the grit for which their fans yearn when they scored four runs in the bottom of the 13th to wipe out a four-run A’s top of that inning. They went 4-for-17 with runners in scoring position, and had they not prevailed, this would have been an immensely painful defeat.

For Mesa, though, it could have been worse. This is no elite prospect. This is a 25-year-old who sat on the Yankees’ bench for 10 games before getting summoned for game action.

This could have been a career-defining gaffe.

“It was a [poorly timed] mistake, but we won,” Mesa said. “That’s what matters.”

This didn’t mark the first time Girardi alerted him to a pinch-running assignment, Mesa said. Yet the prior scenarios didn’t work out. When Chavez singled to right-center field, Mesa made his entrance. He advanced to second on Derek Jeter’s sacrifice bunt, and the A’s opted to intentionally walk Ichiro and go after Rodriguez.

On Rodriguez’s hit, “I just missed third base,” he said. He realized it and tripped as he returned to the bag, thwarting his team’s rally.

“I’ll give him credit. He didn’t compound the problem by continuing to go [home],” Girardi said. “He went back to third base. Because I’m sure everyone would’ve seen it. He would’ve been called out.”

Never before, Mesa said, had he managed to miss third base while running.

Raul Ibanez, the Yankees’ offensive stud of the day with two homers (including a game-tying, two-run blast off Pat Neshek in the 13th), was preparing to play first base in the 15th, thanks to the Mesa-for-Chavez substitution, as the game’s final moments played out.

“You feel for him,” Ibanez said of Mesa. “That’s his debut. At the same time, it’s baseball. It worked out great for him and great for us.”

His teammates immediately comforted him.

Said Mesa: “They just told me, ‘Welcome to the big leagues. It’s not the only game you’re going to play. Just keep your head up.’ ”

Mesa might not have much of a big-league career in his future. But at least he won’t be remembered for the wrong reasons. He will have that lineup card and a memory at which he can smile.